Field
The present invention relates to a pressure transducer simulator that is configured for use with a pressure sensor device and a patient monitoring device. The pressure transducer simulator may be configured to generate a simulation of the output of an analog pressure sensing device to be compatible with the patient monitoring device.
Relevant Background
A standard analog pressure device for measuring blood pressure (typically known as a Disposable Pressure Transducer or DPT) includes a pressure transducer, which is basically a bridge circuit in which a reference signal is applied to one branch of the bridge and the pressure signal is obtained on the other branch. The pressure sensing element (typically a piezoelectric sensor) is placed in one, two, three or four of the four arms of the bridge. The pressure sensing element is basically a variable resistance that varies with the applied pressure. The analog pressure sensing device is usually connected through a fluid filled system to a catheter placed in a vein or an artery, where the pressure pulsations are captured by the pressure sensing element. The analog pressure sensing device is typically for blood pressure monitoring.
The other side of the analog pressure sensing device is typically connected to a measurement instrument, typically a bedside monitor, a blood pressure monitor, or any other monitor that uses the blood pressure signal (e.g., pulse contour Cardiac Output monitors). A reference signal to the analog pressure sensing device is typically provided by the measurement instrument and it is typically used by the instrument to scale the measured blood pressure signal. Different monitors have different reference signals. The reference signal may be either DC or AC and may be typically in the 1-10 Volt range. In AC-based instruments, the operating frequency typically ranges from a few kHz up to 5 kHz.
Unfortunately, standard monitors are generally configured to only interact with particular types of analog pressure sensing devices (e.g., blood pressure devices) and cannot interact with waveforms from other types of pressure sensing devices, such as digital non-invasive blood pressure monitors (NIBMs).